The invention relates to the electrophotographic imaging arts. It finds particular application to a method and system of sensing a voltage applied to a fuser. It will be appreciated that the present invention will find application in printers, copiers, facsimile machines or other electrophotographic imaging devices that fuse an image to a print media.
In electrophotographic imaging devices, toner particles are used to form a desired image on print medium, which is usually some type of paper. Once the toner particles are applied to the paper, the paper is advanced along a paper path to a fuser. In many printers, copiers and other electrophotographic printing devices, the fuser includes a heated fusing roller engaged by a mating pressure roller. As the paper passes between the rollers, toner particles are fused to the paper through a process of heat and pressure.
Electro-mechanical sensors are typically mounted along the paper path to monitor the presence of the paper. When a paper jam occurs, the imaging device can locate or isolate the location of the paper based on the sensors. Typically, an electro-mechanical sensor is mounted before and/or after the fuser to determine whether the paper is in the fuser. Although it is helpful to know the location of the paper, each sensor adds cost to the imaging device.
The present invention provides a new and useful fuser sensing method and system.
In accordance with one embodiment of the present invention, an imaging device is provided that includes an image generation and transfer system that generates an image from toner particles and transfers the image to a print media. A fuser fuses the image to the print media and includes a fuser roller and a pressure roller in pressure engagement with the fuser roller where the print media passes in between. A bias voltage is applied to the fuser to reduce toner particles from being attracted to the fuser. A fuser sensor measures the bias voltage across the fuser and generates a status signal indicating whether the print media is in the fuser based on the measured bias voltage.
In accordance with another embodiment of the present invention, a method of determining a location of a print media within an electrophotographic imaging device is provided. The print media is moved through the imaging device while an image is generated and transferred to the print media. A bias voltage is applied to a fuser to charge the fuser where the fuser bias voltage is affected by the print media contacting the fuser. The image is fused to the print media. The fuser bias voltage is measured and it is determined whether the print media is in the fuser based on the measured fuser bias voltage.
One advantage of the present invention is that an imaging device can determine if a sheet of print media is in the fuser by measuring the bias voltage of the fuser.
Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the illustrated embodiments.